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Management of Tailings Storage Facilities June 2019

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Management of Tailings Storage Facilities June 2019 Management of Tailings Storage Facilities June 2019 1 The failure of the tailings facility at circumstances or regulations – the Córrego do Feijão iron ore as well as regular inspections mine in Brumadinho, Brazil, in and formal annual Engineer of January was a tragedy that left Record reviews. close to 300 people dead and impacted many families and their After the Brumadinho tragedy, communities. Our hearts go out to Gold Fields' operations carried those affected and we have out additional safety inspections offered our deepest condolences at our facilities and concluded and support. that Gold Fields-managed TSFs were not at risk. To further But we also recognise that, as improve operational safety of miners, our responsibilities go our TSFs, we are, where beyond offering just words. We practical, evaluating the have to ensure that we manage potential to move away from the our tailings facilities with the construction of upstream utmost care to avoid a repeat of facilities to centre-line or the Brumadinho tragedy as well downstream designs, as other mine tailings dam failures considering filtered and dry before then. stacked tailings, as well as in-pit tailings disposal. In the wake of the tragedies, Gold Fields is pursuing two broad We will continue to review and, strategies to further strengthen where applicable and practical, the technical management and consider the adoption of leading governance of the 34 tailings practices in the design, facilities at our operations and construction, operation and joint ventures. closure (including post-closure) of tailings dams in the company. At industry level, CEOs of the Gold Fields fully supports International Council on Mining & greater transparency in the Opening Metals (ICMM), including Gold mining sector and as such we Fields, have committed to are today providing a written remarks creating a step change for the response to a request from the by industry in the safety of tailings Church of England Pensions facilities. The ICMM, UN Board and the Swedish Council Gold Fields Environment and the UN on Ethics for the AP Funds to a Principles for Responsible number of listed mining CEO Investment are developing a companies. recognised international standard Nick Holland for member companies, based on At Gold Fields the safety and best practices to ensure that health of our workforce has tailings facility risks are managed always been management’s top appropriately, consistently, and priority. The recent industry transparently. An independent tragedies around the panel of experts is overseeing the catastrophic failures of tailings work. facilities has highlighted once again that the safety of our At company level, Gold Fields has surrounding communities is aligned its tailings management equally critical. practices to the ICMM position statements on water and tailings Sincerely management. All Gold Fields’ TSFs, as well as associated pipeline and pumping Nick Holland infrastructure, are subject to an CEO, Gold Fields Ltd independent, external audit every three years – or more frequently where required by local 2 CHURCH OF ENGLAND PENSIONS BOARD / SWEDISH NATIONAL PENSION FUNDS COUNCIL ON ETHICS REQUEST FOR INFORMATION CONCERNING TAILINGS MANAGEMENT PREAMBLE a) Provide an overview of your tailings management system, and how you manage risk The most significant waste materials produced by our operations are tailings, waste rock, chemical waste and hydrocarbon waste. By managing these wastes responsibly, we minimise the environmental and potential social impact, so as to maintain our licence to operate. In total, as at 7 June 2019, our ten operations (including three joint venture sites) contain 34 tailings dams, of which 14 are active or are being rehabilitated and one will be commissioned imminently. With regards to active tailing storage facilities (TSFs), Gold Fields currently has two in-pit tailings dams operating at Agnew (Australia) and St Ives (Australia), five downstream/centreline tailings dams and seven upstream tailings dams. Gold Fields operations with active downstream/centreline tailings dams are Cerro Corona (Peru), Damang (Ghana) and Tarkwa (Ghana). Gold Fields has only three operations where upstream tailings are being used, being South Deep (South Africa), Tarkwa and Granny Smith (Australia). The factor of safety (FOS) of each existing upstream TSF is regularly reviewed, and when required, modification options (e.g. embankment buttressing) are considered to ensure Gold Fields’ target minimum FOSs are at least sustained. Maintaining our TSFs, which includes identifying, assessing and managing the risks associated with them (including operational, structural and environmental risks) is part of our ordinary course of business. That notwithstanding, Gold Fields, like many other mining companies faces inherent risks in our operation of TSFs. Most critically, tailings must be disposed of in an appropriate manner so as not to impact the safety of the workforce and communities or cause environmental damage. The use of TSFs exposes Gold Fields to certain risks, among them seepage of decanted tailings water or acid mine drainage and the failure of a dam at a tailings storage facility. TSFs designed with upstream constructed embankments typically present greater risk, particularly where the facility is located in a high seasonal rainfall area and where the embankments are constructed using reclaimed tailings materials. The occurrence of a dam failure at one of Gold Fields’ TSFs could also lead to the loss of human life and/or extensive property, environmental damage and result in significant financial exposure and the approach we take to prevent such a failure is described on the following pages. Gold Fields’ Group, regional and mine management regularly assess the risks facing the business. The assessments of the risks and their mitigating actions are a critical internal management tool, which seek to mitigate the identified risks. Risk mitigations are included in the annual Group Performance Scorecard and cascaded down to the performance scorecard of management employees at regional and operational levels. The formal risk review process starts during management’s annual strategic planning sessions where strategic risks and macro-trends are analysed in developing Gold Fields’ risk registers and mitigating actions. These are updated quarterly, and presented to the Board’s Risk Sub-Committee twice a year for verification. Gold Fields maintains measures to manage its TSFs’ safety, including compliance with the International Council on Mining & Metals’ (ICMM) Tailings Governance Position Statement and undertakes routine reviews by independent international consulting companies. All of our operations have tailings management plans in place, including closure and post-closure management plans. Gold Fields has implemented a multi-layered approach to TSF management that includes: 1. TSFs are designed by external, experienced and qualified engineers 2. TSF designs are required to be peer-reviewed 3. Construction is supervised or monitored by the design engineer and includes appropriate quality assurance/control 4. “As-built” facilities are required to be signed-off by the design engineer 5. TSFs are managed by assigned personnel 6. TSFs have an engineer of record appointed who undertakes regular reviews of the TSFs 3 7. Independent audits are undertaken at least on a triannual basis (more often in some cases) 8. Gold Fields’ corporate technical services team review and check TSF management processes employed at the operations 9. Key variances identified by TSF reviews are noted and communicated to the Gold Fields Executive Committee and the Board of Directors quarterly 10. Gold Fields has developed a formal Group TSF Management Guideline, and full compliance to this is expected 11. Risk is identified formally through risk assessments undertaken at various stages of the design and operational process 12. A strategic risk register is maintained at corporate level, which includes risks linked to the TSFs Gold Fields is moving away from installing new upstream TSFs with the most recent new TSFs constructed being in-pit TSFs (Agnew and St Ives), and downstream TSFs (Gruyere (Australia), Tarkwa and Damang). As two of our sites - South Deep and Granny Smith - are located in relatively dry regions, limited amounts of water need to be stored on the facilities, significantly reducing the risk of saturation of the dams. Tarkwa’s upstream tailings dams in Ghana have been constructed from imported fill materials, and are designed assuming worst-case scenario conditions, to ensure the embankments remain stable throughout both the wet and dry seasons, as well as for the life of the facility. All Gold Fields’ TSFs, as well as associated pipeline and pumping infrastructure, are subject to an independent, external audit every three years – or more frequently where required by local circumstances or regulations – as well as regular inspections and formal annual or quarterly Engineer of Record reviews. Risk tables and heat maps have been published in the Integrated Annual Report (IAR) for the last nine years. See https://www.goldfields.com/reports/annual-report-2018/risks-and-materiality.php for more details. Information about how Gold Fields discloses risks associated with its TSFs may be found in its most recent Form 20-F filing with the US Securities and Exchange Commission. See https://www.goldfields.com/form-20- f.php for more details. b) Confirm whether your approach to tailings management has
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